Tooth Count

The total number of teeth on a blade affects the quality and speed of the cut.

• The higher the tooth count, the finer the cut.

• The lower the tooth count, the faster the cut.

• The thicker the wood, the fewer the number of teeth required. 

• Rule of thumb: when the blade is embedded in the wood, two to four of the teeth should be "hidden" (see illustration).

• A higher tooth count is necessary for cutting plastic and metal.

Hook Angle

The hook (or rake) angle of a tooth is the angle formed between the tooth face and an imaginary perpendicular line drawn from the centre of the blade.

• Hook angle is positive if the tooth tip leans towards (crosses) the perpendicular line: max. +30°

• Hook angle is zero if the tooth face lies along the imaginary line: 0°

• Hook angle is negative if the tooth tip leans away from (does not touch) the imaginary line: max. -7°

• A steep hook angle (e.g. +22°) is more aggressive and will pull the wood. This type of angle is usually found on table saw blades.

• A low to negative hook angle (e.g. -6°) reduces the blade's pull on the material. This is the type of angle found on blades for mitre saws, radial-arm saws and circular saws.

• Negative hook angles are essential for cutting metal and recommended for plastic and wood moulding.

Tooth Shape and Configuration

Saw blades can have varying tooth shapes and configurations. Each configuration has its advantages and disadvantages. To choose the right configuration for your task, you will need to consider the material you are cutting, the quality of finish, and how fast you want to cut. 

FTG: Flat Top Grind

• Flat-faced teeth which cut across the whole width of the saw line (the "kerf").

• Cuts fast (each tooth cuts 100% of the width of the notch) but also leaves a rougher finish.

• Ideal for cutting efficiently along the wood grain and through non-ferrous metals.

• Ideal for demolition work

• Configuration often found on circular saw blades

• Generally durable and economical

ATB: Alternate Top Bevel

• Alternating bevel pattern which cuts the wood fibres on one side, then on the other

• Each tooth cuts on one side only, i.e. 50% of the kerf.

• Does not cut as fast as a flat top grind but provides a better finish.

• Cuts effectively both across and along the grain.

• For cutting wood floor planks, plywood, pine studs and oriented strand board (OSB).

• Typically found on crosscut blades and all-purpose blades.Especially effective when used on mitre saws and circular saws.

• Less durable than FTG blades (tend to chip more easily).

TCG: Triple Chip Grind

• Composed of two different-shaped teeth.

• One of the teeth is slightly higher than the other and is bevelled at 45° on both corners, to carve into the

• material down the centre of the kerf.

• The other tooth has a flat top, which cleans out the material that the bevelled tooth has not removed.

• Keeps overheating to a minimum, which extends the life of the blade.

• Recommended for cutting heat-sensitive materials.

• Cuts smoothly and cleanly through hard materials such as kitchen counters, melamine, hardwood and MDF.

• Can be used to cut aluminium.

• Cuts more slowly than the other configurations.

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BLADE TYPES

Blades are designed either for a specific type of application or to perform a combination of tasks ("all-purpose").

For a given cutting operation, you might find a blade for a table saw, circular saw, mitre saw or radial-arm saw.

Some blades can be used on more than one saw; others cannot. 

Manufacturers will often indicate the recommended saw type and use on the blade itself or the packaging. If not, the following information can be used as a guide to determine if the blade can be used on your saw and for which applications:

• Blade diameter: must match the recommended diameter for your saw.

• Arbor diameter: must match the arbor size on your saw

• Hook angle: follow the recommendations given previously regarding saw types and materials.

• Maximum rotation speed (RPM): must be equal to or higher than the speed specified by the saw manufacturer.

• Number of teeth: the higher the tooth count, the finer the cut, but the slower the cut.

• Tooth configuration: if no information is provided, simply look at the teeth to see how they are shaped.

 

Generally speaking, a 6 1/2" or 7  1/4" blade is designed for use on a circular saw  A 10" blade is the usual size for table saws and for sliding compound mitre saws. Some mitre saws and radial-arm saws require blades of 12" or more.